This invention relates to a valve, and more particularly to a valve assembly including a valve body having a movable valve member, and an actuator adapted for engagement with the valve body for providing movement of the valve member within the valve body.
Valves are used in a number of applications to control fluid flow. One type of valve includes a valve body within which a movable valve member is located. The valve body includes an inlet port adapted to communicate with a fluid supply conduit, and an outlet port adapted to communicate with an outlet conduit. Movement of the valve member is operable to open or close the outlet port, to selectively enable fluid flow through the outlet port. In another embodiment, the valve body includes a pair of inlet ports and an outlet port. The valve member is operable to selectively close one of the inlet ports, to enable communication between the outlet port and the open inlet port.
The valve member is mounted to an operating member such as a valve stem, which is pivotably mounted to the valve body. The valve stem is accessible from the exterior of the valve body. The actuator assembly includes a motor and a drive mechanism engaged with the valve stem, such that operation of the motor functions to impart rotation to the valve stem to control the position of the valve member within the interior of the valve body.
The actuator assembly may be either permanently secured to the valve body or releasably engaged with the valve body. Permanent mounting of the actuator to the valve body is disadvantageous in that the entire valve assembly including the valve body must be removed when the actuator assembly requires service or replacement. Releasable engagement of the valve actuator assembly with the valve body has the advantage of enabling the actuator assembly to be freely removed and replaced independent of the valve body, such that the valve body remains in place when the actuator is remover for repair or replacement.
It is an object of the present invention to provide a valve actuator having a number of advantages in construction, operation and assembly over prior art valve actuators. It is a further object of the invention to provide a valve actuator which can be easily engaged with and disengaged from the valve body. It is another object of the invention to provide such a valve actuator which can easily be placed in a proper position relative to the valve body and which ensures a secure connection of the valve actuator to the valve body. Another object of the invention is to provide such a valve actuator which includes an easily operated latch mechanism for engaging the valve actuator with the valve body, and disengaging the valve actuator from the valve body. Yet another object of the invention is to provide such a valve actuator which is relatively simple in its components and construction, yet which enhances operation and assembly of the valve actuator. Yet another object of the invention is to provide such a valve actuator which has a construction that facilitates dissipation of heat from the valve actuator during operation.
In accordance with the present invention, a valve assembly includes a valve body having a valve member with a connector portion, such as a valve stem, accessible from the exterior of the valve body, in combination with a valve actuator which includes a motor and a drive mechanism.
The valve actuator is configured so as to be releasably engageable with the valve body, to enable the valve actuator to be engaged with and removed from the valve body. The valve body includes an outwardly extending mounting member, and the valve actuator is releasably engageable with the mounting member so as to provide releasable engagement of the valve actuator with the valve body. The valve actuator includes a latch member which is movable between a latching position and a release position, for selectively enabling the valve actuator to be engaged with the valve body and removed from the valve body. The valve actuator includes a passage within which the mounting member is received. The mounting member includes a slot, and the latch member includes a latching portion having blocking structure that engages the slot when the mounting member is received within the passage, to prevent removal of the valve actuator from the valve body. The latch member is designed such that, when the latch member is in its release position, the blocking structure is removed from engagement with the slot, to enable the valve actuator to be removed from the valve body. The latch member is spring biased toward its latching position, such that the blocking structure normally prevents engagement of the valve actuator with the valve body until the latch member is moved to its release position, which enables the mounting member to be received within the valve actuator passage. The latch member includes an actuator portion which enables the latch member to be moved to its release position via manual engagement by a user. When the user releases engagement with the latch member actuator portion, the spring bias of the latch member returns the latch member to its latching position to secure the valve actuator to the valve body via engagement of the latch member with the mounting member.
The valve actuator includes a gear housing within which one or more drive gears are mounted, including an output gear that is engageable with the operating member. The one or more drive gears are mounted within an internal cavity defined by the housing, and a motor mounting member is configured to overlie at least a portion of the internal cavity. A motor is secured to the motor mounting member, and includes a motor output member that is engageable with the one or more drive gears so as to impart movement to the operating member in response to operation of the one or more drive gears through the motor output member. In one form, the motor mounting member is in the form of a motor mounting plate configured to overlie substantially the entirety of the internal cavity defined by the housing. The motor mounting member includes one or more upstanding walls that are exposed to the exterior of the valve actuator. The motor mounting member is formed of a heat conductive material such as metal, and the one or more upstanding walls function to dissipate heat, generated by operation of the motor, to the exterior of the valve actuator. The valve actuator is preferably releasably engageable with the valve body via a latch mechanism, having a construction as summarized above, incorporated into the gear housing of the valve actuator.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.